subtract · Example MCP Server MCP: Risk & Policy

WHAT IT DOES

What subtract does on Example MCP Server

AI agents invoke subtract to trigger actions in Example MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why subtract needs a policy

The tool executes a mathematical operation (subtraction) on two inputs. It has no data read/write/delete side effects and involves no financial transactions. It falls under Execute as it performs a computation, though the blast radius is minimal since it only returns a numeric result.

From the tool's definition 'Subtract two numbers' — performs a arithmetic computation operation

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

subtract Rate-limited

subtract stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "subtract": {
      "limits": [
        {
          "counter": "subtract_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Example MCP Server, so you can run agents against it safely.

FAQ

Questions about subtract

What does the subtract tool do? +

Subtract two numbers. It is categorised as a Execute tool in the Example MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on subtract? +

Register the Example MCP Server MCP server in PolicyLayer and add a rule for subtract: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Example MCP Server. Nothing to install.

What risk level is subtract? +

subtract is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit subtract? +

Yes. Add a rate_limit block to the subtract rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block subtract completely? +

Set action: deny in the PolicyLayer policy for subtract. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides subtract? +

subtract is provided by the Example MCP Server MCP server (joseph19820124/joseph_mcp_server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.